There would be some similarity to yours but ours would be made to drive up to a sprout and cut if off after cleaning up around it with my 4' Power Trac brush cutter. We have a bunch of young eastern cedars up to 4" that we need to get down along areas not farmed and also along fences. We also have groves of what I call willows that my 4' brush cutter chokes on. Those individual sprouts the brush cutter can't handle are what we would be targeting.
The shielding and the drive motor would be similar but it would have a circular type saw blade and be attached to an extension of my 2" hitch receiver plate. We may have to add some bracing on it although that remains to be seen.
We're thinking a 12" (or 14" if feasible) circular saw blade would let us cut our way into the cedars so we can see enough of the trunk to cut them down. We could than cut each down and the few that are bigger we would fell with a chain saw.